Coiling die



March 5, '1957 T. woLF 2,783,816

COILING DIE Filed Feb. 14, 1955 United States PatentY "ice COILING DIE Tobin Wolf, Bloomiield, N. J., assigner to Westinghouse Electric Corporation, East Pittsburgh, Pa., a corporation of Pennsylvania Application February 14, 1955, Serial No.-4S8,048

3 Claims. (Cl. 153-67) The present invention relates to coil rwinding machines of the retractable mandrel type for Athe manufacture of coils vhaving vlegs parallel te the coil axis and, more particularly, to an improved ceiling die for such 4a machine.

Although the ceiling die of the present invention may -be employed in the wind-ing of either line lament Wire inte a primary coil or 'a coiled coil likewise employing fine wire for the primary continuous Winding thereof, A'the invention (although not limited thereto) may be illustrated in the manufacture of triple wound coils. Such triple wound coils may be employed, for example, vas -a 100 watt krapid start tiuorescent lamp filament. The primary or first winding of such a coil may consist of a 0.001" diameter tungsten filament wire Wound on a continuous ceiling machine around two stacked mandrels, namely, ya tungsten mandrel of about 0.005" vdiameter and a molybdenum mandrel of about 0.0.0.7" diameter. The secondary winding is then performed on a continuous ceiling machine by Winding the primary winding around, for example, a 0.012l molybdenum mandrel. It will be understood that both the primary and secondary `windings, being performed on a continuous ceiling machine do not employ the retractable mandrel type of ceiling die of the invention. The tertiary or final winding is performed on a retractable mandrel type coil winding machine by winding the secondary or double wound coil (coiled coil) around, for example, an 0.060 retractable molybdenum mandrel.

The -conventional ceiling die heretofore employed for the tertiary winding comprises essentially two cylindrical segments of unequal size. One of the segments may be provided with an axial (coil winding) mandrel guide slet of generally circular er square cross section. The other half segment -is provided with a radially olf-center linsert er guide slot for mounting therein a tungsten carbide guide. Acoil guide slot is provided adjacent to the guide mounting slot. In addition, the entrance end of the, coil guide slot and the insert mounting slot are .machined or cut away in the form of a funnel to permit the threading of the coil into the -coil guide slot.

During coil winding with the above described ceiling die the rigid coiled coil with 4its three mandrels, is frictionally dragged over the tungsten carbide guide. Considerable abrasion results, particularly in the form of eroded filament wire. The wear results in wire breakage or sections having an undesirably smaller diameter. From a consideration of the ydimensions involved it is apparent that even slight abrasion may .result in, for example, an 0.0001" or a 10% reduction in wire diameter. In addition, due to the frictional drag of the small diameter wire being guided around the tungsten carbide insert undue pull or tension on the 'wire often results.

In the case of the tertiary winding it has been found advantageous to feed the secondary winding which is to be coiled parallel to the mandrel. The coil, Vfor example, must be bent transversely in a horizontal plane about 90 from the coil guide slot -axis se that it is fed to the man- 2,783,816 jatentetl Mar. 5, k1-957 drel tangent to the periphery thereof. When the coil characteristic :requirements demand that the radius ofthe bend be kept to a minimum the unusually stiness'of such a coiled coil vrenders .such a condition -extremely diicult to attain.

According to the invention it has been found-'advantageous to employ an improved ceiling Ydie having a nearly frictionless guide, such as a miniature 'or microb'allbear-ing, :instead `of a tungsten carbide guide. A,Although in this instance the force exerted bythe fcoi-led coil during ceiling is almost completely parallel to the end face or periphery of the ballbearing, some .frictional contact does occur between the coil and the mandrel guide hele segment of the ceiling die and perhaps the y'opposite side wall of the coil `guide hole.

Secondly, acoiling die of the invention composed of cylindrical sectors having V-shaped abutting registering surfaces may be employed. The bottom face .of the coil guide mounting 'sector may be provided with intersecting guide mounting slots essentially parallel to the V-shaped portion of fthe mandrel .guide sectors. Nearly frictionless guides, such as microb:allbearings, maybe mounted within 'the guide :slots `se that the wire, or coil, .is carried entirely :by the guides. -In this instance vthe same ceiling die 'may be used for winding either a left or a right helix coil.

ln its general .aspect the present invention has as its objective Ian improved ceiling die for a coil 'Winding `machine ef the retractable mandrel type for producing coils havin-g legs lparallel to the coil axis.

A specific object 'of the present invention is an improved ceiling die for a retractable mandrel type machine which .eliminates abrasion between the wire tor-coil undergoing coil winding and the ceiling die.

A specific object is a ceiling die for a retractable mandrel type machine having a mandrel guide hole cylindrical :segment and a coil guide cylindrical segment being provided with .a frictionless guide mounting slot and a coil guide slot and having .a nearly frictionless guide in said guide mounting slot in engagement with the coil undergoing Winding so that the force exert-ed on the coil during winding is very nearly, but not completely, parallel to the faceo'f the guide and `the frictional drag on the coil is limited to contact with the adjacent face of the mandrel guide hole segment and the opposite side wall of the coil guide slot.

An additional object is a ceiling die for a retractable mandrel type machine .having a mandrel guide hole cylindrical sector .and a coil guide mounting cylindrical sector being provided with inclined intersect-ing coil guide mounting slots, and having nearly frictionless guides mounted in said guide mounting slots with the coil support-ed entirely therebetween to completely eliminate frictional abrasion or rubbing and to provide either left or right helical winding of the coil thereon..

Other objects of the invention will become apparent to those skilled in the art to which it appertaius as the description thereof proceeds both by direction recitation and by implication from the context.

Referring new to the drawing in which like numerals -of reference indicate similar parts throughout the several views:

Fig. .1 is a front elevational view of Ia portion of :a coil winding machine partly in section wherein fthe improved ceiling die of the invention `is incorporated.

Fig. 2 is, an enlarged side elevational view of one embodiment of the ceiling die of the invention on line II-.II of Fig. l in the direction of the arrows.

Fig. 3 is a vertical sectional view of the ceiling die of Fig. .2, along the line .lil-III of Fig;V 2 vin the direction of the arrows.

Fig. 4 is an alternative embodiment of the coiling die ofthe invention.

Fig. 5 is a side elevational view of the alternative embodiment of the coiling dieV of Fig. 4. i Fig. 6 is a front elevational View ofa continuous coiled coil or secondarily wound coil which is fedv into the Y machine of Fig. 1. i

Referring now to the drawing and particularly to Fig. 1, the reference numeral 10 designates a portion,

-for example, of a coiling machine of the retractable ydrel 16 (about 0.012" diameter molybdenum).

The modied primary coiling machine shown in Fig. 1 is an improvement of the type machine disclosed in U. S. Patent No. 2,179,296 entitled Filament Coiling Machine which issued on November 7, 1939, to F. B. Iden and assigned to the General Electric Company. It

.will be understood, however, that this type of machine is disclosed merely as a means of examplifying the improved coiling die of the invention which, it will be understood, may be employed with other types of coil winding machines such as a primary or a secondary coil winding machine of the retractable mandrel type.

The tertiary coiling machine 10 consists essentially of a frame 18 and a coiling mechanism 20 mounted thereon.

,The coiling mechanism 20 may comprise a coil bobbin assembly 22, a coil feed assembly 24, a coiling die of the invention and a coiling head assembly 26, all mounted as hereinafter explained on the frame 18.

Coil bobbn assembly The bobbin assembly 22 (Fig. 1) has a coil bobbin iixed to the outer end of a shaft 32. The shaft 32 is suitably journalled in a bushing carried by a laterally extending wire assembly support arm or angle 34. The support arm 34 in turn is carried by a coiling die holder carriage 38 which is slidable in slidable guides 40 provided in a block 43, which is mounted on the frame 18.

Coil feed assembly 24 The coil feed assembly 24 has a coil guide head provided with an upper stationary jaw 42 and a lower movable jaw 44 for pushing the continuous coiled coil 12 through either a coiling die 25a (Figs. 2 and 3) or 25b (Figs. 4 and 5) of the invention, secured in a coiling die holder portion 52 on the right hand end (when viewed in Fig. 1) of the carriage 38, as by means of a set screw. The upperiixed jaw 42 is mounted on the carriage 38.

.The lower movable jaw 44 is carried on the upper end of a spring biased rod 46. The lower jaw 44 is moved upwardly to grip the coiled coil 12 by the upward movement of a block 48 which is slidably` mounted on the lower end of the rod 46 and retained thereon by means of a collar 49 on the lower end of the rod 46. This block 48 engages the spring on the rod 46 and is also secured to a rod 50 of rectangular cross section which is slidably mounted in a suitable slot in the side face of the carriage 38. A suitable spring (not shown) around the lower portions of the rod 50 separates the block 4S from the depending portion of the carriage 38. A roller 52' carried by an upstanding yoke 54 engages the underside of the block 48. The yoke 54 in turn is mounted on a horizontal generally U-shaped arm 56 which is pivotable at its right hand end (when viewed in Fig. 1) on a horizontal ,1 rod 58 extending between suitable brackets outstanding from a primary coiling head pedestal 60 on the frame 18 arsasie f of the machine 10. The arm 56 is connected by a lever 62 to vertical reciprocating means (not shown) such as a cam mechanism. y

Coling head The coiling head 26 is carried on the left hand end (when viewed inFig. 1) of a hollow rotatable spindle which is journalled in the pedestal 60. A mandrel chuck rod 72 is suitably longitudinally keyed to the spindle 70 and is reciprocable within the spindle 70. The head 26 is suitably provided with a hollow slotted nose 76 having a block thereon and through which a retractable coiling mandrel 78 projects. The coiling head 26 carries a spring biased primary wire clamp lever 80 suitably pivoted thereon. The left hand end (when viewed in Fig. 1) of this lever 80 normally rests in a slot in the nose 76 and is actuated through spring action and the movement of an adjacentA overhanging vertical arm 82. This arm S2 is secured, as by bolts, to an arm 84 on the horizontal Vrod 56.

The hollow spindle 70 is connected to a primary coiling head rotating mechanism not shown). The mandrel 78 is held by a suitable chuck (not shown) on the mandrel chuck rod 72 within the hollow spindle 70 and is actuated by means of a mandrel reciprocating mechanism (not shown).

Colz'ng dies v guide hole segment 100 and a coil guide segment 102 in the case of the tertiary winding selected for illustration purposes only. As shown particularly in Fig. 2 the mandrel guide hole segment 100 is provided with a longitudinal mandrel guide hole 104 into which the mandrel 7S is inserted.

The coil guide segment 102 is provided with an annular guide hole slot 106. A nearly frictionless guide 108, suitably a miniature or micro-ballbearing, is rotatable within the slot 106-on a suitable pin 110 projecting from the segment 102 and into the slot 106. A longitudinal coil slot or hole 112 for the continuous coiled coil 12 is provided above the guide 108. The coiled coil 12 engages the periphery of the frictionless guide 108 as it emerges from the coil hole 112 and is bent transversely (Fig. 2) in a vertical plane through a relatively sharp Vbend and is fed to the mandrel 7S tangent-to the periphery of said mandrel.

v The force exerted by the coiled coil 12 on the periphery of the guide 108 during the coiling thereof about the mandrel 78 is generally nearly, but not completely in a plane parallel to the face of the frictionless guide 108 and hence a rolling force, not a force transverse to said face (i. e. an abrasive force). The coil 12 does frictionally engage slightly the adjacent face of the mandrel guide hole segment 100.

Alternative embodiment of coiling die As shown particularly in Figs. 4 and 5 an alternative embodiment 25b of the coiling die of the invention may comprise two mating portions, namely, an almost sectorlike cylindrical mandrel guide hole portion or sector 200, provided with a mandrel guide hole 201 for the mandrel 78 and a guide mounting portion or sector 202. The bottom face of the guide mounting sector 202 is provided with a pair of intersecting guide slots 204 extending generally parallel to the abutting V-shaped upper faces of the bottom mandrel guide hole sector 200. Pins 208 project from the guide sector 202 into the slots 204. Nearly frictionless guides 210, such as micro-ballbearings, are rotatable on the shafts 208 within the slots 204. As shown particularly in Fig. 4, the continuous coiled coil 12 is carried entirely in the V formed by the guides 210, thus entirely eliminating abrasion or frictional rubbing between the coiled coil 12 and any portion of the die 25b.y

Anf

avisame It should be noted that the coiled coil 12 may be wrapped or wound about the mandrel 78 in either a clockwise (as shown in Fig. or a counterclockwise direction to produce either a left or right hand helical coil.

Thus, it will be seen from the foregoing description that the present invention has provided an improved coiling die 25a or 25b for a coil winding machine of the retractable mandrel type. The improved coiling die either 25a or 25b eliminates abrasion between, for example, a wire, a continuous coil or continuous coiled coil 12 being wound into a coil on the coiling die.

The improved coiling die 25a of the invention has a mandrel guide hole cylindrical segment 100 and a wire or coil guide mounting cylindrical segment 102 provided with a frictionless guide mounting slot 106 and a wire or coil guide slot 112 and has a nearly frictionless guide 108 in said slot 106 for engagement with the wire or coil 12. Through this arrangement, the force exerted on the wire or coil 12 during the coiling thereof is nearly, but not completely, parallel to the periphery of the guide 108. Frictional transverse dragging of the wire or coil 12 on the guide 108 is practically eliminated. Drag is limited to occasional contact with the adjacent face of mandrel guide hole die segment 100 and the side portions of the wire slot 112 in the wire guide segment 102.

An alternative embodiment 25b of the coiling die of the invention ha-s a mandrel guide hole cylindrical sector 200 and a guide mounting cylindrical sector 202 in suitable V-shaped registry. The guide mounting sector 202 is provided with annular intersecting frictionless guide mounting slots 204. Frictionless guides 210 are mounted in the slots 206 with the wire or coil 12 supported entirely therebetween, this completely eliminating frictional abra-sion or rubbing of the wire or coil 12. In addition, the coiling die 25b provides either a left or right helical winding of the coil thereon.

Although a preferred embodiment of the invention has been disclosed it will be understood that modifications may be made within the spirit and scope of the invention.

I claim:

1. A coiling die for a coil winding machine of the retractable mandrel type for winding a continuous coil into a coil having legs parallel to the coil axis and comprising a mandrel guide hole portion and a coil guide mounting portion and a nearly frictionless cylindrical guide pivoted in said coil guide mounting portion to engage said coil tangent to a portion of the periphery thereof and in a plane parallel to a face of said guide to provide nearly frictionles-s rolling contact therebetween and to eliminate transverse dragging Iaction therebetween.

2. A coiling die for a coil winding machine of the retractable mandrel type for winding a continuous coil into a coil having legs parallel to the coil axis and comprising a mandrel guide hole cylindrical segment .and a coil guide mounting cylindrical segment, said coil guide segment being provided with a nearly frictionless guide mounting slot and a coil guide slot, and a nearly frictionless guide in said mounting yslot in engagement with said continuous coil undergoing winding so that the force exerted by said coil on said guide during winding is in a plane parallel to a face of said guide and the frictional drag on said continuous coil is limited to contact with an adjacent face of said mandrel guide hole segment and the opposite side wall of said coil guide slot.

3. A coiling die for a coil winding machine of the retractable mandrel type for winding a continuous coil into a coil having legs parallel to the coil axis and comprising a mandrel guide hole cylindrical sector anda coil guide mounting cylindrical sector, said coil guide mounting sector being provided with inclined intersecting coil guide mounting slots, and a nearly frictionless guide mounted in each of said slots so that said continuous coil undergoing winding is supported entirely Ibetween said guides thus eliminating frictional abrasion of said continuous coil on said guides.

References Cited in the le of this patent UNITED STATES PATENTS 890,907 Horsley June 16, 1908 1,458,997 Sleeper June 19, 1923 1,771,927 Illingworth July 29, 1930 2,179,296 Iden Nov. 7, 1939 FOREIGN PATENTS 80,902 Germany May 4. 1895 514,247 Great Britain Nov. 2, 1939 

